Process for protecting a substrate with an n{11 -pyrimidylamino-arylsulfonamide intumercent agent

ABSTRACT

Intumescent compositions of the invention comprise certain N4pyrimidylaminoarylsulfonamides, such as the N4-2-, 4-, and 5pyrimidylsulfanilamides. The intumescent agents may be employed in conjunction with additives conventionally used in intumescent compositions. For use in protecting substrates from heat and fire, the intumescent compositions may be applied in any suitable manner, such as by electrodeposition, spraying onto an adhesive substrate, or application of a coating composition comprising the intumescent agent.

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United @tatt Roth PROCESS FOR PROTECTING A SUBSTRATE WITH AN N PYRIMIDYLAMINO- ARYLSULFONAMIDE INTUMERCENT AGENT Inventor: Shirley H. Roth, Highland Park, NJ.

Cities Service Company, New York, N.Y.

Filed: Feb. 28, 1972 Appl. No.: 230,135

Assignee:

U.S. Cl. 117/136, 106/15 FP Int. Cl. C09d 5/18, C09k 3/28 Field of Search 117/136; 252/8.1;

References Cited UNITED STATES PATENTS 8/1947 Ludwig et a1. 260/239.95 X 3/1969 Short 260/239.75 12/1964 Schoepke et a1. 260/239.75 X

' 51 NOV.27,1973

3,535,130 10/1970 Webb 117/136 X 3,663,464 5/1972 Sawko 117/136 X 3,707,554 12/1972 Hardy 117/136 X OTHER PUBLICATIONS Maggiolo, Chem. Abs, No. 2551-c (1952), Vol. 46.

Primary Examiner-William D. Martin Assistant Examiner-Harry J. Gwinnell Attorney-Richard S. Stricklcr et a1.

[57] ABSTRACT '7 Claims, No Drawings sEARcH oom PROCESS FOR PROTECTING A SUBSTRATE WITH AN N O9 -PYR IMIDYLAMINO-ARYLSULFONAMIDE INTUMERCENT AGENT BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to intumescent compositions and more particularly relates to such compositions containing a one-component intumescent agent.

2. Description of the Prior Art It is known that a substrate may be protected from heat and fire by the application of an intumescent composition. Intumescent compositions of the prior art usually contain an intumescent agent having at least three components; i.e., a carbonific, a spumific, and a catalyst; and they are typically characterized by the disadvantages of high cost, low spreading rate, relatively poor efficiency, poor water resistance, and poor weather-ability.

As disclosed in U. S. Pat. No. 3,535,130, it has already been discovered that a one-component intumescent agent has advantages over multicomponent intumescent agents. However, the intumescent agents of the patent have poor adherence to substrates and have an undesirable degree of moisture sensitivity.

SUMMARY OF THE INVENTION An object of this invention is to provide a novel class of one-component intumescent agents.

Another object is to provide such intumescent agents having good efficiency and a low level of moisture sensitivity.

These and other objects are attained by using as intumescent agents compounds corresponding to the formula:

wherein Ar is a divalent aromatic residue, R is a pyrimidyl or substituted pyrimidyl radical, and R is hydrogen, hydrocarbon, substituted hydrocarbon, or acyl.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The intumescent agents of the invention may be any compounds corresponding to the above formula. However, they are preferably compounds wherein Ar is a divalent aromatic residue derived from benzene or naphthalene or an alkyl, haloalkyl, alkoxy, haloalkoxy, halo, hydroxy, carboxy, amino, amido, or nitro derivative thereof. When the aromatic ring bears organic substituents, it is usually preferred that these substituents contain one-five carbon atoms' When there are halo substituents, it is usually preferred that they be chloro or bromo. It is also preferred that the aromatic ring have at least one free reactive position.

R of the above formula is preferably a pyrimidyl radical, but it may bear one or more substituents if desired. The substituted pyrimidyl radicals most commonly found in these compounds are the chloro, bromo, carboxy, hydroxy, amino, thio, sulfonamido, C,-C alkyl, C 43 alkoxy, phenyl, and benzo derivatives, but compounds Containing other substituted pyrimidyl radicals are also utilizable. When R is a substituted pyrimidyl radical, the nitrogen of the ar-amino group may be attached directly to the pyrimidine ring, or it may be attached to the pyrimidine ring through the substituent.

As indicated above, R may be hydrogen or a hydrocarbon, substituted hydrocarbon, or acyl radical, preferably hydrogen or a C C alkyl, phenyl, aminophenyl, sulfonamidophenyl, nitrophenyl, or acetyl radical.

Exemplary of the intumescent agents of the invention are N -2-pyrimidylsulfanilamide, N-4- pyrimidylsulfanilamide, N-5-pyrimidylsulfanilamide, 4-(2-pyrimidyl)amino-3-chlorobenzenesulfonamide, 2-(2-pyrimidyl)amin0-4-bromobenzenesulfonamide, 4-(2-pyrimidyl)-amino-2-ethylbenzenesulfonamide, 3-(2-pyrimidyl)amino-4-chloromethylbenzenesulfonamide, 4-(2-pirimidyl)amino-Z-butoxybenzenesulfonamide, 4-(2-pyrimidyl)amino-3-chloromethoxybenzenesulfonamide, 4-(2-pyrimidyl)amino-3-hydroxybenzenesulfonamide, 4-(2-primidyl)arnino-3-carboxybenzenesulfonamide, 4(2-pyrimidyl )amino-3- aminobenzenesulfonamide, 4-(2-pyrimidyl)amino-2- amino-2-acetamido-benzenesulfonamide, 2-( 2 pyrimidyl)amino-4-nitrobenzene-sulfonamide, N -(5- chloro-Z-pyrimidyl)sulfanilamide, N-(5-bromo-4,6- dimethyl-Z-pyrimidyl)sulfanilamide, N-(4-carboxy-2- pyrimidyl)sulfanilamide, N-(4-hydroxy-2- pyrimidyl)sulfanilamide, N-(2-amino-5- pyrimidyl)sulfanilamide, N"-(4-amino-2- pyfimidyUsulfanilamide, N-(2-ethylthio-4-methyl-6- pyrimidyl)sulfanilamide, N,N" -2,4-pyrimidylbis-sulfanilamide, N-(4-methyl-2- pyrimidyl )-sulfanilarnide, N-( 2-methoxy-5' pyrimidyl)sulfanilamide, N-(4-phenyl-2- pyrimidyl)sulfanilamide, N-2-benzopyrimidylsulfanilamide, N ethyl-N -2-pyrimidyl sulfanilamide, N'-

'(4-aminophenyl)-N -2-pyrimidylsulfanilamide, N -(4- sulfonamidophenyl)-N -2-pyrimidylsulfanilamide, N- (4-nitrophenyl)-N-2-pyrimidylsulfanilamide, N- acetyl-N-2-pyrimidylsulfanilamide, the corresponding naphthalene compounds, etc. When not readily available, these compounds may be prepared by known techniques.

For use in protecting a substrate from heat and fire, the intumescent agen'.s of the invention may be applied in any suitable manner, e.g., electrodeposition, spraying of powdered intumescent agent onto an adhesive substrate, etc. However, it is usually preferred to compound the intumescent agent with a binder, e.g., nitrocellulose, and optionally also with one or more of the other ingredients conventionally used in intumescent compositions, e.g., stabilizers, dispersing agents, pigments, driers, biocides, anti-foamers, thickeners, protective colloids, fillers, blowing agents, etc.; disperse the composition in a suitable liquid medium, e.g., water or a solvent or solvent mixture; and apply the coating composition thus formed to the substrate to be protected. As is the case with conventional intumescent coating compositions, it is frequently convenient to apply these coating compositions in the form of a paint having a solids content of about IO% by weight and an intumescent agent/binder weight ratio of about 0.075l4/l to deposit a coating having a dry thickness of about O.()Ol-0.75 inch.

The intumescent agents of the invention are efficient, have low moisture sensitivity, and intumesce to form foams having good volume, cell structure, and adherence to substrates, such as wood, metal, and plastics.

They are also useful as flame retardants in normally flammable compositions.

The following example is given to illustrate the invention and is not intended as a limitation thereof.

I EXAMPLE I Place one gram of N-2-pyrimidylsulfanilamide in an aluminum pan and flame it with a propane torch. The compound intumesces to form an excellent volume of foam having a good cell structure. I

Similar results are also observed when N-4- pyrimidylsulfanilamide, N -5-pyrimidylsulfanilamide, and the other intumescent agents mentioned in the specification are substituted for the intumescent agent of the Example.

It is obvious that many variations may be made in the products and processes set forth above without departing from the spirit and scope of this invention.

What is claimed is:

l. A process for protecting a substrate from heat and fire which comprises applying thereto an intumescent composition comprising as the intumescent agent a I compound corresponding to the formula:

wherein Ar is a divalent aromatic residue, R is a pyrimidyl or substituted pyrimidyl radicaLand R is hydrogen, hydrocarbon, substituted hydrocarbon, or acyl.

2. The process of claim 1 wherein Ar is a divalent aromatic residue derived from benzene or naphthalene or an alkyl, haloalkyl, alkoxy, haloalkoxy, halo, hydroxy, carboxy, amino, amido, or nitro derivative thereof.

3. The process of claim I wherein R is a pyrimidyl radical or an an alkyl, amino, sulfonamido,.or thio derivative thereof.

4. The process of claim 1 wherein R is hydrogen, alkyl, phenyl, aminophenyl, sulfonamidophenyl, nitrophenyl, or acetyl.

5. The process of claim l wherein the intumescent agent is N -2-pyrimidylsulfanilamide.

6. The process of claim 1 wherein the intumescent agent N-4-pyrimidylsulfanilamide.

7. The process of claim 1 wherein the intumescent agent is N -5-pyrimidylsulfanilamide.

P011050 UNITED E5'.l./\TES PATENT OFFICE GER i it WA 1 in 05* QORRELQ i MN Pat n 2771152 7 Dated November 279973 Inventor(s) Shirley H. ROth It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

, 1 (E over page fi rst column line 4, "IN UMERCENT" should be INTUMESCENT Column l, line ,2, "N" should be N column l, line 3, "09" should be deleted; column l line 4, "INTUMERCEN'T" should be INTUMESCENT column l l ine 20, "er-ability" should be erability Column 2,

l ine l6 "pi rimidyl should be pyrimidyl I column 2, line l9, "primidyl should be pyrimidyl column 2, line 22, "amino-2" should be deleted. Column 4, line' 22, after "agent" 1's should be inserted.

Signed and sealed this 2nd day of April 197L EAL) Attes t:

EDWARD MJ LETCHER, JR. C; l LARSHA LL DANN Atte sting Officer Commissionerof Patents 

2. The process of claim 1 wherein Ar is a divalent aromatic residue derived from benzene or naphthalene or an alkyl, haloalkyl, alkoxy, haloalkoxy, halo, hydroxy, carboxy, amino, amido, or nitro derivative thereof.
 3. The process of claim 1 wherein R is a pyrimidyl radical or an an alkyl, amino, sulfonamido, or thio derivative thereof.
 4. The process of claim 1 wherein R'' is hydrogen, alkyl, phenyl, aminophenyl, sulfonamidophenyl, nitrophenyl, or acetyl.
 5. The process of claim 1 wherein the intumescent agent is N4-2-pyrimidylsulfanilamide.
 6. The process of claim 1 wherein the intumescent agent N4-4-pyrimidylsulfanilamide.
 7. The process of claim 1 wherein the intumescent agent is N4-5-pyrimidylsulfanilamide. 